US6620999B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for controlling electromagnetic radiation emissions from electronic enclosures
Assignee: Hewlett Packard Development Co LP
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Filing: 2001-06-15
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Granted: 2003-09-16
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Expires: 2021-06-15
Abstract
Abstract A method and apparatus is provided for reducing electromagnetic radiation emissions. The method and apparatus of the present invention also reduce or prevent electromagnetic radiation generated by sources outside of a system assembly from interfering with and adversely affecting electrical circuits in the assembly. An electromagnetic compatibility (EMC) solution uses a lossy element, and/or an element comprised of a combination of lossy and conductive material.
Inventors
- 👤 David Pommerenke
- 👤 David Dickey
- 👤 James J. DeBlanc
- 👤 Victoria Tsang Tam
- 👤 Kenneth K. Tang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 20:27
CPC Classifications
H; H05; H05K; H05K9/00; H05K9/0062
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
146 words
An assembly, comprising: an enclosure having opposing side walls, a top, and a bottom, the enclosure having an aperture formed by opposing flanges; a module configured to integrate with the enclosure, the module having opposing side walls, a top, and a bottom, that substantially surround electrical circuitry, wherein a gap is formed between an outer surface of the module and the opposing flanges of the enclosure; a low-impedance contact disposed between an outer surface of the module and the enclosure, the contact having a length at least one-fourth the wavelength of a transition frequency, the contact electrically coupling the module to the enclosure, wherein those portions of the outer surface of the module and the enclosure that overlap the low-impedance contact comprise materials selected from the group consisting of metal, conductive plastic, and plastic with a metallization layer; and a lossy element disposed in the gap.
Claim 2
Dependent Claim
146 words
An assembly, comprising: an enclosure having opposing side walls, a top, and a bottom, the enclosure having an aperture formed by opposing flanges; a module configured to integrate with the enclosure, the module having opposing side walls, a top, and a bottom, that substantially surround electrical circuitry, wherein a gap is formed between an outer surface of the module and the opposing flanges of the enclosure; a low-impedance contact disposed between an outer surface of the module and the enclosure, the contact having a length at least one-fourth the wavelength of a transition frequency, the contact electrically coupling the module to the enclosure, wherein those portions of the outer surface of the module and the enclosure that overlap the low-impedance contact comprise materials selected from the group consisting of metal, conductive plastic, and plastic with a metallization layer; and a lossy element disposed in the gap.
Claim 3
Dependent Claim
19 words
The assembly of claim 1 , wherein the lossy element is fixed to an outer surface of the module.
Claim 4
Dependent Claim
19 words
The assembly of claim 1 , wherein the lossy element is fixed to an inner surface of the enclosure.
Claim 5
Dependent Claim
21 words
The assembly of claim 1 , wherein the lossy element has a depth that approximates the length of the low-impedance contact.
Claim 6
Dependent Claim
21 words
The assembly of claim 1 , wherein the lossy element comprises a material that both absorbs and reflects high-frequency electromagnetic energy.
Claim 7
Dependent Claim
17 words
The assembly of claim 5 , wherein the lossy element comprises a material that is electrically conductive.
Claim 8
Dependent Claim
18 words
The assembly of claim 1 , wherein the lossy element comprises a sheet manufactured from a dielectrically-lossy polyethylene.
Claim 9
Dependent Claim
18 words
The assembly of claim 1 , wherein the lossy element comprises a pad manufactured from a dielectrically-lossy polyethylene.
Claim 10
Dependent Claim
21 words
The assembly of claim 1 , wherein the enclosure further comprises a transverse internal wall configured with at least one opening.
Claim 11
Dependent Claim
24 words
The assembly of claim 9 , wherein the transverse internal wall comprises a layer of lossy material on the surface adjacent to the module.
Claim 12
Dependent Claim
14 words
The assembly of claim 1 , wherein the lossy material comprises a dielectrically-lossy polyethylene.
Claim 13
Dependent Claim
26 words
The assembly of claim 11 , wherein the lossy material comprises a material selected from the group consisting of conductive polyethylene, conductive rubber and magnetically-filledsilicon rubber.
Claim 14
Dependent Claim
13 words
The assembly of claim 11 , wherein the lossy element comprises a gasket.
Claim 15
Dependent Claim
31 words
The assembly of claim 1 , wherein electromagnetic energy of frequencies approximately above the transition frequency are prevented from traversing the gap by being reflected and attenuated by the lossy material.
Claim 16
Dependent Claim
26 words
The assembly of claim 1 , wherein electromagnetic energy of frequencies approximately below the transition frequency are prevented from traversing the gap via conventional electrical conduction.
Claim 17
Dependent Claim
88 words
An assembly, comprising: a first means for preventing electromagnetic energy of a frequency approximately below a transition frequency from traversing a gap formed by the outer surface of a module and opposing flanges of an enclosure, the first means comprising a low-impedance contact having a length that is at least one-fourth the wavelength of the transition frequency; and a second means for preventing electromagnetic energy of a frequency approximately above a transition frequency from traversing the gap, the second means comprising a lossy element disposed in the gap.
Claim 18
Dependent Claim
88 words
An assembly, comprising: a first means for preventing electromagnetic energy of a frequency approximately below a transition frequency from traversing a gap formed by the outer surface of a module and opposing flanges of an enclosure, the first means comprising a low-impedance contact having a length that is at least one-fourth the wavelength of the transition frequency; and a second means for preventing electromagnetic energy of a frequency approximately above a transition frequency from traversing the gap, the second means comprising a lossy element disposed in the gap.
Claim 19
Dependent Claim
24 words
The assembly of claim 16 , wherein the low impedance contact substantially overlaps an electrically conductive portion of both the module and the enclosure.
Claim 20
Dependent Claim
26 words
The assembly of claim 16 , wherein the lossy element comprises a material selected from the group consisting of conductive polyethylene, conductive rubber, and magnetically-filledsilicon rubber.
Claim 21
Independent Claim
80 words
A method for controlling electromagnetic interference, comprising: providing a low-impedance contact having a length that is at least one-fourth the wavelength of a transition frequency; electrically coupling an electrically conductive assembly enclosure to an electrically conductive module, the enclosure partially surrounding the module, wherein the module substantially surrounds electromagnetic emitting circuits, with the low-impedance contact; and introducing a lossy element in a gap formed by surfaces of the assembly enclosure, the outer surfaces of the module, and the low-impedance contact.
Claim 22
Independent Claim
80 words
A method for controlling electromagnetic interference, comprising: providing a low-impedance contact having a length that is at least one-fourth the wavelength of a transition frequency; electrically coupling an electrically conductive assembly enclosure to an electrically conductive module, the enclosure partially surrounding the module, wherein the module substantially surrounds electromagnetic emitting circuits, with the low-impedance contact; and introducing a lossy element in a gap formed by surfaces of the assembly enclosure, the outer surfaces of the module, and the low-impedance contact.
Claim 23
Dependent Claim
28 words
The method of claim 19 , wherein introducing the at least one lossy element prevents electromagnetic energy of frequencies approximately above a transition frequency from traversing the gap.
Claim 24
Dependent Claim
33 words
The method of claim 19 , wherein electrically coupling an electrically conductive assembly enclosure to an electrically conductive module prevents electromagnetic energy of frequencies approximately below a transition frequency from traversing the gap.
Claim 25
Dependent Claim
32 words
The method of claim 19 , wherein introducing a lossy element comprises a lossy element comprising a material selected from the group consisting of conductive polyethylene, conductive rubber, and magnetically-filled silicon rubber.
Claim 26
Dependent Claim
33 words
The method of claim 19 , wherein providing a low-impedance contact comprises a low-impedance contact comprising a material selected from the group consisting of metal, conductive plastic, and plastic with a metallization layer.
Claim 27
Dependent Claim
32 words
The method of claim 19 , wherein electrically coupling an electrically conductive assembly enclosure to an electrically conductive module comprises arranging the low-impedance contact substantially perpendicular to a surface of the enclosure.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2006-09-15 | 2007-03-17 | 2007-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-09-15 | 2011-03-17 | 2011-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2014-09-15 | 2015-03-17 | 2015-09-16 | $7700.00 | Window Closed / Lapsed |